Finding a way to "ghost" on Facebook generally falls into three categories: browser-based tools, manual stealth methods, and technical extensions. Browser-Based Tools (No Login Required)

If you value your own security, stay away from any software that promises to hack Facebook’s privacy walls.

Now you can browse your newsfeed and check profiles without appearing "online" to your friends list.

If your goal is to look at a friend's profile without them seeing your "Green Dot" online status, you can toggle this off.